Susceptibility of European cultivars of Italian and perennial ryegrass to crown and stem rust F. X. SchubigerJ. BaertB. BayleP. BourdonB. CagasV. Cernoch • E. CzemborF. EickmeyerU. FeuersteinS. HartmannH. Jakesova • D. JohnstonB. KrautzerH. LeenheerH. LellbachC. PerssonW. Pietraszek • U. K. PosseltM. RomaniL. RussiS. SchulzeM. C. TardinF. VanHee •

Abstract A set of 15 Italian (Lolium multiflorum),three hybrid (L. boucheanum) and 33 perennialryegrass (L. perenne) cultivars were evaluated fortheir rust susceptibility in the field. The cultivars weregrown in 2001, 2004 and 2007 at 29, 32 and 27European sites, respectively. Rust incidence wasscored during different growth cycles using a scalefrom one (no rust) to nine (susceptible). Crown rust(Puccinia coronata f. sp. lolii) was the mostfrequently observed rust species on Italian, hybridand perennial ryegrass during all three experimentalyears. There was a highly significant difference inmean crown rust scores among Italian and perennialryegrass cultivars, respectively, in each of the F. X. Schubiger (&) B. BollerAgroscope Reckenholz-Ta¨nikon, Research Station ART,Reckenholzstrasse 191, 8046 Zurich, Switzerlande-mail: franz.schubiger@art.admin.chJ. BaertILVO-Eenheid Plant, 9090 Melle, BelgiumB. BayleDLF Trifolium, 49320 Les Alleuds, FranceP. BourdonS.A. Carneau, 59310 Orchies, FranceB. CagasOSEVA PRO Ltd., Grassland Research Station RoznovZubri, 75654 Zubri, Czech RepublicV. CernochPlant Breeding Station, 74247 Hladke Zivotice,Czech RepublicE. CzemborIHAR Radzikow, 05-870 Blonie, PolandF. EickmeyerSaatzucht Steinach, 94377 Steinach, GermanyU. FeuersteinEuro Grass Breeding GmbH, 27330 Asendorf, GermanyS. HartmannInstitut fu¨r Pflanzenbau u. Pflanzenzu¨chtung derBayerischen Landesanstalt fu¨r Landwirtschaft,85354 Freising, GermanyH. JakesovaPlant Breeding, 74247 Hladke Zivotice,Czech RepublicD. JohnstonN.I. Horticulture and Plant Breeding Station, Loughall,Armagh BT 618 JB, Northern Ireland, UKB. KrautzerBundesanstalt fu¨r alpenla¨ndische LandwirtschaftGumpenstein, 8952 Irdning, AustriaH. LeenheerDLF Trifolium Netherlands B.V., 4727 ST Moerstraten,The NetherlandsH. LellbachBAZ Institut fu¨r Landwirtschaft und Kulturen,18190 Gross Luesewitz, Germany